Furnace.



F. J. NICE.

FURNACE.

APPLICATION FILED r213. 12, 1913.

Patented Dec. 30, 1913.

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w @@@@@M 5 w, H @WQQ w w IHVEHTOR WITHE55E5 W -W ATTORNEY COLUMBIAPLANQGRAPH 6a.. WASHINGTON. D. c.

F. J. NICE.

FURNACE.

APPLICATION FILED FEB; 12, 1913.

Patented Dec. 30, 1913.

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l HVENTOR HTTORHEY COLUMBIA PLANOGRAFH CO.,WASHINUTON, D. c-.

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Patented Dec. 30, 1913.

F. J. NICE.

FURNACE.

APPLIOATIONHIILED r1112. 12, 1913.

IHVEHTQR HTTORHEY WITHEE5 ill A TEN FREDRICK J. NICE, 0F PONTIAC,MICHIGAN.

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Specification of Letters Patent.

Application filed February 12, 1913.

To all whom it may concern:

Be it known that I, FREDRIGK J. NICE, a citizen of the United States,residing at Pontiac, county of Oakland, State of Michigan, have inventeda certain new and useful Improvement in Furnaces, and declare thefollowing to be a full, clear, and exact description of the same, suchas will enable others skilled in the art to which it pertains to makeand use the same, reference being had to the accompanying drawings,which form a part of this specification.

This invention relates to furnaces in general and especially to cruciblefurnaces and has for its object a furnace that is economical inoperation and which attains very high temperatures.

One of the important features of this invention is the preliminaryheating of the pots before they are introduced into the main heatingchamber, so that it is not necessary to melt the metal from a coldcondition.

Another feature is the construction and arrangement of three chamberswhich will be more fully explained hereinafter.

In the drawings :Figure l, is a horizontal section and a plan view ofthe furnace. Fig. 2, is a vertical section lengthwise the furnace. Fig.3, is a vertical cross section of the furnace.

The furnace walls are constructed of fire bricks which have a'maximumcapacity for withstanding high temperatures. The walls are built to formthree chambers, one of which I shall designate the preparatory chamber(indicated as 1), a second, the preparatory-combustion chamber 2, and athird, the main-heating chamber 3 (Fig. 2). Fire bricks extend over thepreparatorycombustion chamber 2, while the main heating chamber 3 isclosed by lids or covers 4 that are provided with handles 5 by whichthey may be lifted off when access to the interior is desired. A burner6 opens into the mouth of the preparatory chamber 1. This is an oilburner and is fed with blown air (pressure about 32 ounces) and oil andcontains suitable regulatory means by which the amount of fuel and airsupply may be regulated to control the heat within the furnace.

The shape and division of the chambers is important. Referring to Fig.1, it is seen that the walls of the furnace near the burner (3 start todiverge, then they run nearly parallel again. These walls inclose thepreparatory or gasifying chamber 1. I am aware that it is not novel touse a space for fuel to be divided and mixed with air, but I am notaware of a use such as my preparatory chamber 1. This chamber is notpart of the burner, but a part of the furnace and is heated by the hot.walls of the furnace and the burning gases rolling back from thepreparatory-combustion chamber 2. This heating, of course, tends to morefully gasify the fuel and put it into condition for ready combustion, sothat a much larger amount of air can be used with a given unit of fuelthan is prescribed by the standards of shoppractice. The next chamber orthat space formed by the Walls again diverging is thepreparatory-combustion chamber. I call it the preparatory-combustionchamber for the reason that some mixture of the air and the fuel takesplace here, although mainly the combustion. This chamber is divided fromthe main heating chamber 3 by the baflie wall 16 which serves to breakup the burning gases and the air rushing in serves to spread the flameinto all parts of the furnace whereby uniformity and intense heat isse-.

cured. The main heating chamber 3 is located beyond the bafiie wall 16and is bounded on the sides by the converging walls, shown in Fig. 1, inthe rear by the rear wall of the furnace and in front by the baffle wall16. The crucibles 15 lie behind the battle wall and are protected fromthe blast from the burner and the fuel is so broken up by thebafiie'wall and spread by the force of the air that it is carried to thecrucibles without injuring them, in fact, the unusual result of againheating crucibles in which the melted steel has been allowed to solidifycan be accomplished. Additional air for combustion is supplied from thecon trollable air pipe 7 to the preparatory chamber 1 through thepassage way 7 that leads from the top of the furnace down at the sidesof the preparatory chamber and thence into the preparatory chamber. Thisair is heated by contact with the hot Wall of the furnace.

Below the main-heating chamber 3 is located the slag pit 8 and this isdivided off from the main-heating chamber 3 by the cast iron floor 9which is supported by the I beams 10. Over the cast iron floor 9 is alayer of ganister or ground fire-brick 11. A slag hole 12 penetratesthrough the ganister and the center of the cast iron floor. Upon thelayer of ganister is packed coke-breeze, indicated at 13. This isprevented from falling through the slag hole 12 by the cover plate 1 1.The slag pit and the slag hole are intended for use when the crucible,cokebreeze or fire bricks slag away under the intense heat. This slagmay be emptied from the main-heating chamber by poking the 7 cover 1 1away from the slag hole 12 and then poking the residuum in the chamberor allowing the slag to run through the hole 12. This operation may alsobecome necessary when one of the pots is spilled or breaks.

The crucibles 15 which are made of plumbago or other heat-resistingmaterial are set in two rows of three each as shown in Fig. 1.

I11 the drawings, I have shown two furnaces grouped together which isone of my preferred forms of construction, but the feature that I amjust about to describe may be employed in connection with a singlefurnace. This feature consists of preventing the radiation of heatbyinsheathing the sides and back of the furnace with lead-away flues.Referring to Fig. 1, the passage way 17 will be noticed at about thecenter of the back of the main heating chamber and the passage way 18will be noted at the side near the back of the main heating chamber.These passage ways lead into the lead-way flue 19 which insheathes theback of the furnace and side and which is almost as deep as themain-heating chamber. This lead-way flue extends on the left side to thefront of the furnace adjacent the burner to a point 20 where it divesbelow the level of the bottom of the main-heating chamber. Similarly alead-way flue leads from the back of the furnace (at the right ofFig. 1) and about the right side to a point 20 where it dives below thelevel of the floor of the mainheating chamber. These two leadaway fluesjoin at 21 in the common flue 22, which discharges into a stack, notshown. The flues serve also to heat the air passages 7 and thepreparatory chamber 1. It will, of course, be understood that the twofiues may insheath one furnace as Well as two.

These oil burning furnaces furnish intense heat and the substances inprocesses of combustion and the products of combustion shoot withgreatforce through the preparatory chamber into the preparatory-combustion chamber and main-heating chamber;

in fact, the flame reaches out through any crevices or openings thatthere may be about the furnace. It is my idea instead of allow ing thesesubstances that are in process of combustion to escape through the finesand thereby lose considerable heat, to conduct them in the form of asheathe about one or all of the chambers so as not only to add to theheat by their proximity to these chambers, but to also form a sheathingfor the sides and back of the furnace to prevent the radiation of theheat that is produced within the chambers. I find that by the useof'this sheathing of the substances in process of combustion and theproducts of combustion that a very high temperature may be attained inmy furnace, in fact, a fairly dark purple heat may be attained.

Each of the crucibles may be filled with from 1410 to 170 pounds ofsteel punchings or other waste steel and the steel in these sixcrucibles for each furnace may be melted in about one hour and fiftyminutes and I find that I have a very high grade of molten steel forcasting. I also find that I can get four and five heatings out of thecrucibles before they become unfit for use, as against three in commonshop-practice.

Another feature of my furnace is that I can enlarge the side lead-awayflues as shown in Fig. 1 and set in each of these six crucibles forpreliminary heating so that when a batch of crucibles in themain-heating chambers or chamber are removed, the crucibles which havebeen preliminarily heated may be set down in the main-heating chamberand the process of melting will be considerably lessened as to time.This is, of course, an economical and important feature for it bothlessens the time in which thefuel is burned and it also lengthens thelife of the crucibles by lessening the time in which they are subjectedto the intense heat of the mainhcating chamber.

Lids 23 cover the side lead-away fiues so that access may be had to thecrucibles 24 that are being preliminarily heated. The covers 4: havefeed-holes 25, stopped by pieces of brick 26. These are used to lookinto each crucible and to feed any constituent through when desired.

I have described the shape of my furnace, the sheathing, the chambers,etc., with reference to a crucible furnace, but it may be easily adaptedfor other furnace work and I do not want to be limited to cruciblefurnaces alone, but want to be understood as claiming the structurewherein my newly discovered principles are introduced as applied to alluses.

IVhat I claim is 1. A furnace, having in combination, walls shaped toform a narrow preparatory chamber, at one end of which the walls divergeto form a preparatory-combustion chamber and a battle wall separatingsaid preparatory combustion chamber from a larger substantiallyrectangular chamber that forms a main heating chamber, the said wallsbeing also formed with leadaway fiues which lead from a passage way atthe back of the main combustion chamber on either side of the mainheating chamber, the preparatory combustion chamber and preparatorychamber to the front of the furnace, the said leadaway fiuescommunicating with the main heating chamber on at least one side andbeing of the depth sufficient to substantially insheathe the said threechambers, a burner located at the end of the preparatory chamberopposite the preparatory combustion chamber, and covers removablyattached to the furnace walls so that access can be had to the mainheating chamber and also to the leadaway flues whereby the leadawayflues may be used for preliminary heating as well as insheathing of thechambers to prevent radiation of heat, substantially as described.

2. A furnace comprising refractory material forming a narrow preparatorychamber,

a preparatory combustion chamber beyond said preparatory chamber andformed by the walls diverging from the walls of the preparatory chamberand a substantially rectangular main heating chamber located beyond thepreparatory combustion chamber and divided therefrom by a battle wall,the said refractory material forming also passage ways leading down fromthe top of the furnace on either side of the preparatory chamber anddischarging thereinto, a burner FREDRIGK J. NICE.

Witnesses:

STUART O. BARNES, AMELIA C. KOEHN.

copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

